Conventionally, as an electric connection box, an electric connection box described in Patent Document 1 is known. In this electric connection box, a circuit component is housed in a casing. The circuit component is formed by insert-molding plural bus bars arranged at intervals using a synthetic resin material. An electronic component is connected, by soldering or the like, to exposed sections of the bus bars exposed from the synthetic resin.
In the synthetic resin section, through holes are formed in positions corresponding to positions among the bus bars adjacent to one another. The through holes are formed to cut tie bars that couple the bus bars adjacent to one another.
Patent Document 1    Japanese Patent Laid-Open No. 2004-120837
However, according to the configuration explained above, spaces are formed by the through holes among the adjacent bus bars. The air has relatively low thermal conductivity. Therefore, it is apprehended that sections in contact with the air in the through holes of the bus bars are filled with heat generated from the bus bars during energization and the bus bars are locally heated. Then, it is apprehended that connection reliability in, for example, soldered sections of the bus bars and the electronic component falls.
There is a need in the art to provide an electric connection box that is suppressed from being locally heated.